Method for producing stainless steel powder containing nitrogen high nitrogen by adopting gas atomization method

Abstract

The invention belongs to the field of powder metallurgy, and particularly relates to a method for preparing nitrogen-containing / high-nitrogen stainless steel powder using a gas atomization method. Including ingredients required according to the alloy design; placing the granular or massive high-nitrogen alloy in a secondary feeder, and adding the remaining ingredients to the melting furnace; smelting in a vacuum and / or non-vacuum atmosphere; and obtaining molten steel by stirring after it is melted Add high-nitrogen alloy to the molten steel with uniform composition; heat it up to 1500℃~1750℃ to start atomization, the atomization medium is nitrogen, and the pressure is 1.0~10MPa; after the powder is cooled, it is sieved and vacuum packed as needed. The invention has the characteristics of relatively simple equipment, easy operation, high production efficiency and low cost. It can produce stainless steel powders of different alloy systems with high purity, controllable nitrogen content and good fluidity.

Description

Technical field [0001] The invention belongs to the field of powder metallurgy, and particularly relates to a method for preparing nitrogen-containing / high-nitrogen stainless steel powder using a gas atomization method. Background technique [0002] In the 1930s and late 1940s, the shortage of nickel resources stimulated research on using nitrogen to replace nickel in the preparation of stainless steel. Researchers have found that nitrogen can not only improve the strength of steel materials, but also has an important impact on improving the corrosion resistance of materials, especially resistance to chloride ion pitting corrosion. In addition, foreign studies in recent years have shown that nickel ions are a potential allergenic factor that can induce toxic effects near implants in the body, cause cell destruction and inflammatory reactions, and have teratogenic and carcinogenic hazards to the organism. Nickel ions affect 10-20% of women and 6% of men in the United States ...

AI Technical Summary

Problems solved by technology

[0010] The disadvantage of high-pressure nitrogen smelting-nitrogen atomization method is that high-pressure equipment is required, and there are disadvantages such as expensive and complicated equipment, high-pressure danger, difficult process control and high production cost.

[0011] The disadvantage of the fluidized bed powder nitriding method is that the microstructure of the nitriding powder is uneven, the oxygen content is high, and the energy consumption is high; the disadvantage of the mechanical alloying method is that the powder morphology is lamellar, the fluidity is poor, and the nitrogen content is not easy to control

[0012] In order to solve the problems in the production of nitrogen-containing stainless steel, such as expensive and complex equipment, high-pressure danger, difficult process control, high production cost, and poor powder fluidity, and to avoid other problems in the preparation of nitrogen-containing / high-nitrogen stainless steel powder, the present invention proposes a Method for preparing nitrogen-containing / high-nitrogen stainless steel powder by gas atomization process

Images